You guys aren't realizing that a Jinchuriki with Uchiha blood would only be about half as strong as the sum of it's parts, because BOTH controling the Tail Beast and the Sharingan take massive amounts of training and practice. They would need to spend at least twice the amount of time training, more because I don't think the two powers are quite compatible (From what I can tell the Kyubi hates Uchihas)